Gators aren't the reason you aren't supposed to swim in the lakes in Florida, it's the brain-eating amoebae.
We saw one in the water surrounding Tom Sawyer island. It was kinda creepy, to say the least.
Never seen a gator, although DH is always looking. I did see an armadillo while riding the bus back to the resort late one night. I was rather excited. It was the first time I'd seen a live one outside of a zoo.